You have no items in your shopping cart.

2% online discount, easy
payment by credit card
Fast delivery, reduced
costs from 150 €
More than
100k products

Rings and stoppers are useful aids in the daily lab routine. Manufacturers like Bohlender, Deutsch&Neumann, Bürkle and Duran produce stoppers and rings for various types of vessels, flasks and valves. Stoppers are made of fluoroplastics (e.g. PTFE), silicone or glass. Further stoppers are available in numerous shapes with variable top and bottom diameter, with a middle hole or a lamella-like grinding.  

Here you find further information on fluoroplastics

Product was successfully added to your shopping cart.

Rings & Stoppers

Set Ascending Direction

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  1. Duran Group

    Pouring ring/PP, green 10 pcs., 10 pcs.

    SKU: DU1089911
    In Stock
  2. Duran Group

    Pouring ring/PP, yellow 10 pcs., 10 pcs.

    SKU: DU1089917
    In Stock
  3. Duran Group

    Stopper NS 24/29 for WERTEX safety connectors

    SKU: DU247960304
    In Stock
  4. Duran Group

    Pouring ring/PP, blue for DIN-thread GL 32, 10 pcs.

    SKU: DU292421907
    In Stock
  5. Heinz Herenz

    Steristopfen 13mm, Zellstoff, 1000 St/Pk

    SKU: HZ1011300
    In Stock
  6. IDL GmbH

    Cork stopper H x diam. top/bottommm 18x10x7 100 pcs.

    SKU: ID2400111050
    In Stock
  7. IDL GmbH

    Cork stopper, H x diam. top/bottom mm 26x20x17 100 pcs.

    SKU: ID2400111150
    In Stock
  8. Dinkelberg Analytics

    Hollow glass stopper, pointed, NS 14,5

    SKU: SE8690004
  9. Dinkelberg Analytics

    Steristopfen 12 mm, Zellstoff, 1000 St./Pk

    SKU: HZ1011200
    In Stock
  10. Heinz Herenz

    Steristopfen 14 mm, Zellstoff, 1000 St./Pk

    SKU: HZ1011400
    In Stock
  11. Hirschmann

    SILICOSEN natural C55

    SKU: HI8905755
  12. Duran Group

    Pouring ring/PP, gray 10 pcs., 10 pcs.

    SKU: DU1089914
  13. Duran Group

    Pouring ring, PTFE, 5 pcs.

    SKU: DU1167307
  14. Duran Group

    PE plastic stopper 14/23 10 pcs., 10 pcs.

    SKU: DU292040603
  15. Duran Group

    PE plastic stopper 29/32 10 pcs., 10 pcs.

    SKU: DU292040903
  16. Duran Group

    PE plastic stopper 45/40 PE plastic stopper 45/40

    SKU: DU292041205
  17. Duran Group

    Pouring ring/PP, blue for DIN-thread GL 45, 10 pcs.

    SKU: DU292422809
    In Stock
  18. Duran Group

    Pouring ring/ETFE, red for DIN-thread GL 45, 10 pcs.

    SKU: DU292442802
  19. Duran Group

    Seal PTFE-coated, GL 18 for red screw caps, 10 pcs.

    SKU: DU292481107
  20. Duran Group

    Seal PTFE-coated, GL 45 for red screw caps, 10 pcs.

    SKU: DU292482806
  21. Supelco

    SEALING RESIN, 5GM, 1 pc

    SKU: SU23817
  22. Dinkelberg Analytics

    Steristopfen 16mm, 5000 St./Pkg

    SKU: HZ1011600
  23. Dinkelberg Analytics

    Steristopfen 45 mm, Zellstoff, 300 St./Pk

    SKU: HZ1014501
  24. IDL GmbH

    Cork ring 210 X 150 X 30 MM

    SKU: ID2400202100
  25. Hirschmann

    Poly stopper (PE) NS 7/16

    SKU: HI8900252
  26. Hirschmann

    Poly stopper (PE) NS 10/19

    SKU: HI8900260
  27. Hirschmann

    Poly stopper (PE) NS 12/21

    SKU: HI8900265
  28. Hirschmann

    Poly stopper (PE) NS 14/23

    SKU: HI8900270
  29. Hirschmann

    Poly stopper (PE) NS 19/26

    SKU: HI8900275
  30. Hirschmann

    Poly stopper (PE) NS 24/29

    SKU: HI8900280
  31. Hirschmann

    Poly stopper (PE) NS 29/32

    SKU: HI8900286
  32. Hirschmann

    Poly stopper (PE) NS 34/35

    SKU: HI8900290
  33. Hirschmann

    Poly stopper (PE) NS 45/40

    SKU: HI8900293
  34. Hirschmann

    Silicone-stopper SILICOSEN T10 10 pcs.

    SKU: HI8905510
  35. Hirschmann

    Silicone-stopper SILICOSEN T12 10 pcs.

    SKU: HI8905512
  36. Hirschmann

    Silicone-stopper SILICOSEN T15 10 pcs.

    SKU: HI8905515
  37. Hirschmann

    Silicone-stopper SILICOSEN T17 10 pcs.

    SKU: HI8905517
  38. Hirschmann

    Silicone-stopper SILICOSEN T19 10 pcs.

    SKU: HI8905519
  39. Hirschmann

    Silicone-stopper SILICOSEN T22 10 pcs.

    SKU: HI8905522
  40. Hirschmann

    Silicone-stopper SILICOSEN T24 10 pcs.

    SKU: HI8905524
  41. Hirschmann

    SILICOSEN natural T28

    SKU: HI8905528
  42. Hirschmann

    Silicone-stopper SILICOSEN T32 10 pcs.

    SKU: HI8905532
  43. Hirschmann

    SILICOSEN natural T38

    SKU: HI8905538
Set Ascending Direction

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5

Fluoroplastics: Rings & Stoppers made of PTFE, FEP, PFA etc.

Fluoroplastics belong to the family of thermoplastics. The higher the fluoric content, the better the chemical and thermal capacity of fluoropolymers. A number of characteristics makes fluoroplastics an ideal material for rings and stoppers. Unique properties are:

• universal chemical resistance,
• high thermal load capacity (-200 °C up to +260 °C),
• resistance to all sterilisation temperatures,
• resistance to environmental changes (weather, light),
• ultra-low friction coefficient and
• UV-resistance.

Further, accessories made of fluoroplastics are
• non-flammable,
• non-adhesive,
• unbreakable,
• physiologically safe and
• inert, without taste or odour.

In particular, the chemical and thermal resistance of PTFE is remarkable (-260°C up to +300°). The permanent temperature resistance depends on the load, so PTFE can be used from -200°C to +260°C at moderate mechanical load. PTFE lab equipment, e.g. hoses, magnetic stirring bars, bottles, or stirrer shafts, has a white appearance, a non-adhesive surface and extraordinary slip characteristics.

The chemical and mechanical properties of FEP are similar to those of PTFE. However, the upper limit of the permanent working temperature is lower (+205° C). FEP lab supply, e.g. hoses, is translucent to transparent and non-porous.

PFA has similar chemical and thermal characteristics to PTFE. PFA labware, e.g. hoses, bottles, or round-bottom flasks, is translucent to transparent, non-porous and particularly useful in high-purity work.

PP however does not belong to the family of fluoroplastics. PP is autoclavable (at +121° C) and has good mechanical and chemical properties almost up to its softening point. Lab supply made of PP, e.g. olives for stopcocks and valves or also lab furniture, is unbreakable and an economical alternative.

Cleaning of Fluoroplastics

Due to their smooth, non-wetting surface, all fluoroplastics (PTFE, PFA and FEP) can easily be cleaned. However, abrasive scouring agents might damage the surface and result in a milkiness of the vessels. All neutral detergents (pH 7) are suitable, for a stronger contamination an alkaline detergent up to pH 12 is recommended. Vessels should only be cleaned or dryed in laboratory washing machines when they are completely opened. Here you find a selection of cleaners and disinfectants as well as further information. Vessels made of PTFE, PFA or FEP can be autoclaved or sterilised at +121° C. To avoid deformation or destruction, all vessels with screw covers or stoppers have to be open while being autoclaved. Pressurisation (from inside) should be avoided, too due to the thin walls of standard PTFE, PFA or FEP bottles.

Duran Stoppers made of Borosilicate Glass

Stoppers made of borosilicate glass by Duran are an alternative to stoppers made of fluoroplastics. Borosilicate glass 3.3 is resistant to water, neutral and acid solutions, concentrated acids and acid mixtures, chlorine, bromine, iodine and organic substances. Further, borosilicate glass endures temperatures over 100° C and is universally applicable. Hence Duran glass is suitable ideally for the application in laboratories. Only HF-alkylation, concentrated phosphoric acid and strong alkali in combination with high temperatures (>100°C) lead to glass corrosion. For any other application areas e.g. Duran semi-hollow glass flat-head stoppers are available at Analytics-Shop.com.

Go back to products